On October 18, 2022, the government approved the release of genetically modified (GM) mustard hybrid, Dhara Mustard Hybrid (DMH-11) for seed production and also the release of its GM parental lines for developing new parental lines and hybrids before its commercial release.
DMH-11 was developed by Dr Deepak Pental and his team of scientists at Delhi University’s Centre for Genetic Manipulation of Crop Plants in 2000. The institute was set up in 1996 with the help of the ‘Milkman of India’, Dr Verghese Kurien, who arranged for funding through the National Dairy Development Board (NDDB) at Dr Pental’s request. At the time, NDDB was helming ‘Operation Golden Flow’, which was aimed at helping India attain self-sufficiency in production of edible oils. It was part of the Technology Mission on Oilseeds that was launched in 1986 by then Prime Minister Rajiv Gandhi. NDDB had launched the Dhara brand of edible oils, which was sold by the Gujarat Cooperative Milk Marketing Federation (GCMMF).
Dr Pental, who obtained a doctorate from Rutgers, US, in 1978 and a post-doctoral degree from the University of Nottingham, UK, returned to India in 1983 and joined TERI (Tata Energy Research Institute, renamed The Energy and Resources Institute). In 1993 he moved to the genetics department of Delhi University. Since establishing the Centre for Genetic Manipulation of Crop Plants, Dr Pental and his team are credited with several noteworthy research achievements including bollworm resistant GM cotton, mustard which is low in heart-harming erucic acid and elements that give it pungency, and white rust resistant mustard. The team has published more than 40 papers in international scientific journals.
In 2006, Dr Pental and his team developed a conventional method of pollination control in mustard and released the first mustard hybrid, DMH-1. The GM mustard hybrid scores with higher yield—28% higher than the mega variety Varuna. The barnase-barstar system is a versatile method of pollination control in largely self-pollinating mustard over conventional ones. It is expected to increase mustard yields and output, helping the country reduce dependence on imported edible oil.
After the government’s approval, activists opposing GM crops have raised a veritable storm. On November 3, the Supreme Court (SC), acting on two writ petitions filed by anti-GM activists in 2004 and 2005, ordered status quo on the decision of the Genetic Engineering Appraisal Committee that greenlighted commercial cultivation of GM mustard.
The interview has been lightly edited for brevity.
The NGOs opposing GM crops are not consistent. They hold the European Union as an example of countries that oppose GM crop cultivation. But they also oppose the use of herbicides, and the EU is a large user of pesticides including those meant to control plant pests (weeds). It uses on average 3 kg per hectare, whereas India uses 360 gm of pesticide per hectare.
Their attitude has been to spread confusion and fear. They had a favourable five-member TEC (Technical Expert Committee, appointed by the Supreme Court in 2012), which said ban HT (herbicide tolerance) and Bt (Bt gene derived from an agro-bacterium which confers borer resistance), when it was not even in their terms of reference. The terms of reference were to see whether the isolation and biosafety tests were okay and whether we have the wherewithal to do them properly. They are desperate people. Sometimes they say the hybrid (of GM mustard) does not yield that much, sometimes they say it is HT (DMH-11 is herbicide tolerant). Some even compared the yield of European rapeseed with Indian mustard. One is a 10-month crop and the other (Indian mustard) is a four-month crop.
What is the barnase-barstar system?
The mustard flower contains both male and female sexual organs, so it self-pollinates or fertilises itself. To produce hybrid seed, two parents have to be crossed. In DMH-11, the parents are Varuna and Early Heera-2, which have been genetically modified. Varuna bn 3.6 contains the barnase gene linked with the herbicide-tolerant bar gene. EH-2 modbs 2.99 contains the bar gene and the male fertility restoring barstar gene.
The barnase gene makes the pollen unviable for pollination. It makes the Varuna plant male sterile so it cannot self-pollinate and can be fertilised with the pollen of EH-2 modbs 2.99. To produce hybrid seeds in large quantities, there have to be many lines of both parents. Multiple Varuna modbs 3.6 lines are obtained by crossing them with normal Varuna. The resulting progeny will segregate and 50 percent will be male sterile and the rest will be normal, self-pollinating plants. When sprayed with herbicide the self-pollinating plants will die as they don’t have the bar gene.
Multiple EH-2 modbs 2.99 lines are obtained by self-pollinating them. These are in turn crossed with male sterile Varuna plants. After pollination, the EH-2 modbs 2.99 lines are removed from the production plot. The seeds which the remaining plants will produce will be fully fertile DMH-11 hybrid seeds.
Have you figured out what triggers the anti-GM activists, what their motives are?
I have not gone deeply into it. What I feel is that the Left opposed it because patents have become strong on recombinant DNA technologies. Their feeling was that only multinationals will bring these technologies and they will charge very heavily, and the farmer will not benefit, and national food security can get jeopardised. There are others who feel that the environment is so important that you can sacrifice a lot of other things. And there is a third group which believes that everything good has happened in the past. There are different shades of ideologues opposing GM technology. I believe the country must develop expertise in this area and there must be public-funded research.
What I feel is that the Left opposed it because patents have become strong on recombinant DNA technologies. Their feeling was that only multinationals will bring these technologies and they will charge very heavily and farmers will not benefit
Do you see the public sector doing a lot of research in GM crops?
Not a lot. People got demoralised. Also, it is one thing publishing a paper, it is another making a product. We need to put in much more effort. Hopefully, the release of GM mustard will create enthusiasm among younger people.
Have scientists in the public sector been demoralised by the regulatory hurdles?
For sure. But I think the recent actions of the government, both with regard to genome editing and genetic engineering, will lead to much better research from Indian labs. This has to be backed up with monetary resources. [On March 30, 2022, the environment ministry issued an office memorandum that exempted two categories of genome-edited plants, which are free of exogenously introduced DNA, from certain provisions of Rules 1989 of the Environment (Protection) Act, 1986, that govern transgenic crops. In October it notified standard operating procedures for organisations involved in research, development, and handling of such plants. These are meant to facilitate genome-editing work. The government’s approval of GM mustard for seed production is also a departure from its past stance on GM crops.]
Isn’t the Department of Biotechnology funding research programmes in state agricultural universities?
Training among scientists is also lacking. People work in silos. DBT (Department of Biotechnology) institutions are not collaborating properly with ICAR (Indian Council of Agricultural Research), ICAR is not coordinating with DBT institutions…. We will have to use all the talent we have very carefully so that we can achieve some good agricultural goals.
Regarding the Left concern about agricultural MNCs dominating, when you lift the regulatory hurdles don’t you push the science towards companies that are well-funded?
That’s what has happened. There has been huge consolidation in the seed and agrochemical sectors. Research intensity has to increase in our country. China has done that. Not only does it have much better research intensity in agricultural crops, it has also bought Syngenta, one of the leading agrochemical and seed companies. It has covered all its flanks; we have been debating and debating and not doing enough.
You mentioned the other aspect—the environmental impact. Do you think GM technology is compatible with environmentally benign agriculture?
Bt cotton certainly reduced the use of pesticides to control Helicoverpa. The population of Helicoverpa has reduced, leading to saving of crops like pigeonpea (tur dal), which is grown in the same ecologies. Pigeonpea was a difficult crop for farmers due to lack of control of Helicoverpa. What we forget is that each crop has a number of problems, which need independent solutions. Just saying that it (Bt cotton) has not controlled the other insects…it was never meant to control whitefly. It was never meant to control the viral diseases that whitefly spreads. Pectinophora is becoming a big problem. You can solve these problems by doing more research and having your laboratories doing good research.
[The Bt protein in Bt cotton is toxic to Helicoverpa armigera or American bollworm which had developed resistance to pesticides in the 1990s. It is now under control. But Pectinophora gossypiella or Pink bollworm has developed resistance for a variety of reasons. The American bollworm feeds on multiple crops, including pigeonpea. Because of the toxic Bt gene in Bt cotton, its population has reduced which has helped the pigeonpea crop.]
Bt cotton certainly reduced the use of pesticides to control Helicoverpa. The population of Helicoverpa has reduced, leading to saving of crops like pigeonpea (tur dal), which is grown in the same ecologies
While Bt cotton has reduced pesticide use for control of the bollworm, pesticide usage for control of sucking pests has increased.
Sucking pests demand a totally different solution. Maybe molecular drives to reduce their populations. Only science can find solutions to these problems. There are pesticides but insects develop resistance to pesticides also. They develop resistance to a gene-based anti-feedant and they develop resistance to conventional chemical pesticides also. You cannot shy away from finding solutions through science and technology.
There are NGOs who repose greater faith in pre-industrial agricultural ways than in chemical agriculture.
There are so many studies that say you will have yield depression of 30% to 40% for crops grown organically. There is not sufficient manure in the world. Collection is a major issue. You can use human urine to produce urea, but how do you collect it?
Why did you choose mustard for research after doing your doctorate in the US and post-doctoral degree in the UK?
At that time, if you recall, Sam Pitroda was in charge of some national missions. [Pitroda was a telecommunications expert and Prime Minister Rajiv Gandhi’s go-to man for various technology missions.] I felt, let’s try to bring new techniques like somatic cell genetics and transgenics to mustard, which is our own crop, and there will be less competition, you will not have to chase others, you can work at your own pace.
Why did you tap the National Dairy Development Board and before that the Tata Energy Research Institute for funds?
In TERI we were funded by DBT and TERI put a lot of money into hardware. We were able to set up all the protocols for genetic transformation of brassica species, including cauliflower and Brassica nigra (black mustard), which is one of the parents of the Brassica juncea mustard species. [DMH-11 is a cross between Brassica juncea variety Varuna and the East European variety, Early Heera-2.] So that was a good start. But we found that CMS (cytoplasmic male sterility) systems or conventional pollination control systems were not adequate. Some had chlorosis problem (yellowing of the tissue, indicating low photosynthesis efficiency). In some, the restoration (of male fertility after cross-pollination) was not there. Although we published papers, it did not make a viable product. That is when we decided to use the barnase-barstar system, which had been published by Plant Genetics Systems in Belgium, and it worked very well. [The paper was published in Nature journal in 1992.]
When you want to test two parents, you emasculate the male part and pollinate it with the other on a small scale to raise seed to see in which direction that cross is going, is it more productive or not
While your decision to do research in mustard was a considered one, the choice of parents for cross-breeding GM mustard was quite fortuitous because you happened to be in Poland…
A very distinguished professor asked me (at a conference on rapeseed in Poland in 2000) whether I was aware that mustard was grown in the western part of the then Soviet Union, mostly in the Ukraine area. I had no clue. My training was not in mustard breeding [Dr Pental’s PhD was on in vitro morphogenesis of wheat]. He gave me some seeds, and when we crossed those seeds with Indian types we found that there was 30% to 35% yield increase and that is what we wanted to exploit. If the parents on both sides improve, heterosis process will also improve.
You got the 30% increase through conventional breeding?
That (the cross-pollination) was handmade. When you want to test two parents, you emasculate the male part and pollinate it with the other on a small scale to raise seed to see in which direction that cross is going, is it more productive or not. That was the idea behind that study. We found that there was higher productivity than the best Indian parent, Varuna, or even Pusa Bold or other varieties.
You developed a hybrid DMH-1 with cytoplasmic male sterility. Why did you not persist with it?
Because it (male sterility) was unstable. On foggy days, when temperature drops, it starts getting some fertility and that is a disaster. You must have 95% purity of hybrid seed, only then it is a viable commercial product.
The anti-GM activists say there are five conventionally bred mustard hybrids which are 0.6% to 15% higher yielding than GM mustard DMH-11.
The two or three hybrids they are talking about were introduced last year so we don’t know their performance over the stipulated three-year period. Or whether they have been checked for how much sterility is still there. That is also questionable. But the most important point is when you cross East European with Indian types you get heterosis (hybrid vigour): that is the most seminal observation. DMH-1, DMH-11 and DMH-4 are based on that. The good point about DMH-11 is that the pollination control mechanism, which is based on genetic engineering, is much more stable and scalable than 126-1 [126-1 is a cytoplasmic male sterility system which Dr Pental and his team developed in 2006], which is our own. It’s like saying to us that we are stupid, why are we not using 126-1.
We were asked to do tests which no other country has done on the barnase-barstar system. Like post-translational modification of the protein. But we did not mind it and we thought, let all the tests be done
It is what you had developed.
That’s purely our work. This (barnase-barstar) has taken inspiration from others. 126-1 is totally from our lab. If it had worked, we would not have gone into genetic engineering.
In the conventional pollination control system, can you easily develop male sterile Varuna or Kranti lines?
We tried to put 126-1 into other Indian varieties. It turns fertile. It’s only in Pusa Bold that it gives full male sterility. That also breaks down under low temperatures. In other varieties it is partially fertile. There is no way you can diversify. We tried it for so many years.
So, it is not as if you just jumped into genetic modification.
No, not at all. In fact, we tried to make DMH-1 in a firm in Hisar and when we did it on a large scale and could not rogue out (remove) the fertile looking plants, it led to seed impurity.
Other than the activists, even eminent scientists like Dr M.S. Swaminathan have expressed doubts about GM technology.
In the 2004 committee of which he was chairman, male sterility and restoration was one of the key areas scientists were asked to work on. Disease and insect resistance were other areas. Why he changed his mind, I don’t know.
His comments affected your work?
If he had continued to support the technology, things would have happened much earlier. Dr Manmohan Singh, the then prime minister, asked for the second green revolution based on new technologies at the Science Congresses. But some people in his own party were opposed to it and Dr Swaminathan joined them rather than listening to the wisdom of the prime minister.
One of the criticisms is that our regulatory system is not strong.
It asks for too much. In fact, if anything, it does not follow a very progressive approach. It is over-cautious. We were asked to do tests which no other country has done on the barnase-barstar system. Like post-translational modification of the protein. But we did not mind it. This was the first indigenously developed material and we thought, let all the tests be done so that there is satisfaction that everything is ok.
What extra tests were done? There is concern that we are introducing transgenes in food.
Protein stability, heat stability, degradation in the digestive juices, chronic toxicity, acute toxicity, equivalence of the transgenic for all kinds of compounds, minerals, bee visitation…. All kinds of surveys.
The European Union follows the precautionary principle. It thinks no hazard is acceptable. But the major food exporting countries follow the principle of substantial equivalence. Don’t you think that over-caution is needed because we are releasing something into the environment, and we don’t know how it will pan out in the years to come? Isn’t that a valid concern?
To some extent it is. But we have now almost 20 years’ experience with genetically engineered crops and very involved analysis has been done by all kinds of science academies. While individual scientists may not be liking the idea of genetically engineered crops, the broad consensus, including among Nobel Prize winners who wrote to our prime minister (in 2016), is that we should use these technologies. I think they are needed more where the farm size is small, but we have to keep a check on the cost of the technology, and I think to some extent monopolies need to be avoided. Also, the ‘no technology’ notion has to be avoided. Europe can probably afford it. They are buying huge amounts of genetically-engineered cornmeal and soymeal from the US for feeding their animals. That is the wish of a group of countries which are more environment sensitive and do not have any money to make from their crops by exporting them. But US, Latin America, Canada, Australia… these are also very agile countries in terms of science and technology. They have accepted it and so have all the European science academies which have said there is nothing wrong. In Europe, it is a political decision, not a scientific decision.
We have now almost 20 years’ experience with genetically engineered crops and very involved analysis has been done by all kinds of science academies. The broad consensus, including among Nobel Prize winners who wrote to our prime minister (in 2016), is that we should use these technologies
Of the three transgenes in GM mustard, are the barnase-barstar and bar proteins completely eliminated in mustard oil or mustard oil cake?
In oil nothing is present.
Why not?
Because these genes are expressed only in a specific part of the plant. They don’t express in the seed at all. So how will they come into the oil or the seed meal.
What about the leaves…sarson ka saag that people eat?
Only a small amount, traces of bar gene protein (which confers herbicide tolerance).
There is opposition to herbicide tolerance. Is it well founded?
Not at all. What we need is conservation tillage in most of north India. When we harvest rice, we should be able to sow wheat or mustard directly into the rice field. That way we will improve our soils, will not be losing those precious 15 to 20 days of crop growth. In the US plains, they have just turned the corner. States like Kansas had become dust bowls because of over-ploughing. Now with conservation tillage they have rejuvenated their soil, and they are doing very well in terms of production without ruining their soil.
In conservation tillage you save on tractor emissions, but herbicide emissions are released. Don’t they cancel each other out, more or less?
In rice if you want direct seeding, weeds become a big issue. You can either save water and say, I will not use any chemical. Without weedicides there will not be any agriculture, at least in the western countries. Europeans use huge amounts of weedicides. They use selective weedicides. In the US they use non-selective weedicides. You have to use four or five selective weedicides, one kills a particular group of weeds, the other kills another one…. And therefore, you have to be dextrous, see which kind of weed is in the field and pick the right weedicide. Weedicides are going to be there, but regarding fungicides, bactericides, and pesticides for insect pests you can think of some genetic engineering methods and conventional breeding methods, like in wheat rust resistance is being bred for the past 30 to 40 years. Our food security would have been in the pits if rust resistant wheats were not available.
What we need is conservation tillage in most of north India. When we harvest rice, we should be able to sow wheat or mustard directly into the rice field. That way we will improve our soils, will not be losing those precious 15 to 20 days
In mustard itself, is herbicide tolerance a useful trait?
I don’t go that much in the field, so I don’t know what they (farmers) are spraying. I was told they are using some herbicides. But right now, I think we should move in the direction in which the government has by releasing the GM mustard, using herbicide for hybrid seed production plots and not for the fields.
In an article you have said that protection of yields is as or more important than yield enhancement.
You can make a hybrid but if it is prone to all kinds of diseases and insects you will not realise the positive impact of the hybrid heterosis. So, disease and pest resistance should be our top priorities.
Even if the Supreme Court does not interfere in the production of seed, will the overhang of the court case have a sort of chilling effect on the production of hybrid seed, particularly in the private sector?
I think the government decision should be upheld if we want to move forward. Any strictures will create difficulties in commercialisation. This is not a pure line; it is a hybrid and only commercial companies can do hybrid seed production properly.
Have you sought the interest of private companies in the production of GM mustard seed?
A number of them have written to me already.
Have you given them the seeds of the parental lines?
Not yet.
Are you waiting for clarity from the Supreme Court?
Yes. It is better that we get it cleared by the Court. The order said no more planting, which has affected some of the operations we could have done this year. But let’s hope that for the future we have a clear path.